Meteorites are the basis of our understanding of the formation and evolution of the early Solar System. These PhD projects tie in with a larger scale project known as the Global Fireball Observatory. Prof. Tomkins collaborates with scientists at Curtin University and elsewhere to recover newly fallen meteorites across Australia using a widely distributed all-sky camera network and weather radar. His role in this project is to lead expeditions to recover meteorites and to conduct petrological analysis on the new meteorite specimens. This allows linking of specific types of meteorites to their orbital origins. PhD students working in the project will be intimately involved in desert expeditions to recover meteorites, and will use the new meteorites as the foundation of their research, supplemented with existing meteorites as required. Research will focus on using a combination of petrology and geochemistry to improve our understanding of the evolution of asteroids and planets early in the Solar System’s history. Students will be given the flexibility needed, and actively encouraged, to follow their own interests within this broad remit. Students will use the Australian Synchrotron, which is situated adjacent to the Monash University campus, and other advanced facilities as required, including experimental petrology, split stream LA-MC-ICPMS, FEG-microprobe, FEG-SEM, FEG-TEM, laser Raman, XRF, XRCT – all housed within or close to the SEAE.

Recent space missions to asteroids have gathered detailed information not just on the composition of these bodies, but also on their material properties – e.g. their strength, and whether they are a rubble pile or a single monolithic rock. But we know very little about the strength of small objects in the metre to 10s metre class. This project will look at the breakup of meteoroids in our atmosphere to calculate the bulk strengths of these objects, be it by seismic, infrasound or photometry. It will also look at the origins of this material to determine if there is a correlation between strengths and any specific orbits or regions of the Solar System, or specific asteroids and their families. The results will inform our understanding of the asteroid hazard (do small objects all generate airburst ‘Tunguska-like’ explosions), the lifetime of debris in the inner Solar System, and how we date the ages of planetary surfaces.

The Desert Fireball Network (DFN), operated by Curtin consists of a large array of astronomical cameras in the outback to recover fresh meteorites with orbits, by observing incoming meteors, and then searching for the fallen rock. Searching for meteorite falls in the remote outback is a costly activity, traditionally done with teams of people camped on site, searching the area on foot. Recently SSTC has successfully developed a drone-based approach, using machine learning to identify meteorites in aerial imagery, and recovered the first fresh meteorite found with a UAV. This project will focus on continuing this development, using the drone in the field, enhancing it's capability and the system's machine learning abilities to support new terrains and new detection techniques, and as needed to recover fresh meteorites from the DFN. There will also be the opportunity for the applicant to investigate applied uses of this aerial anomaly-detection technology, such as search and rescue or environmental monitoring.